Everybody wants their own app store and cloud, and Valve is no different. The source of many of the greatest games in the past few years (Portal 1 and 2, people!), Valve’s Steam game platform has become renowned for its ease of use in buying games and the Source game engine is no slouch, either.

Steam is about to open up a whole new world of apps beyond games, however. Full blown applications are due to hit the Steam platform September 5, and will range from “creativity to productivity” as Valve’s Mark Richardson is quoted in Forbes.

The Steam mobile app accidentally leaked its own appsplosion last month, showing off categories such as ‘Accounting’ and ‘Photo Editing.’ Obviously a lot of those app categories are useful when making games, and it would be terribly cool if Steam Greenlight was somehow tied to a series of tools for creators to build games that went straight to the store. Steam would, in effect, have an end-to-end ecosystem for game developers.

According to Valve’s statement, its customers want their apps on Steam, and Valve is prepared to let them. Perhaps this is partially motivated by Valve CEO Gabe Newell’s perception of Windows 8 as heading down the road of a closed platform, and Valve wants a foothold? Either way, it’ll be interesting to see what apps appear on Steam.